How can you get vocaloid?

You can get VOCALOIDs from their own companies:

Zero-G ltd.

Dear Stage

PowerFX

Crypton Future Media

I-Style Project

Bplats. Inc

internet Co. Ltd.

AH-soft

YAMAHA (you can even buy all VOCALOIDs from there, including their own VOCALOIDs)

Ki/oon, or Sony Japan

1st Place (It's a company)

SBS Artech

Y2 Project

VoctroLabs